Transmyocardial revascularization system and method of use

ABSTRACT

A transmyocardial revascularization system including a plurality of inserts formed of a material to elicit a healing response in tissue of the myocardium and deployment instruments and associated components for deploying the inserts into the wall of the myocardium. The inserts are arranged to be disposed within respective lumens or channels in the wall of the myocardium. The inserts can take various forms, e.g., be solid members, tubular members, or porous members, and may be resorbable, partially resorbable or non-resorbable. In some embodiments the inserts are arranged to be left in place within the channels in the wall of the myocardium to result in plural lumens which enable blood to flow therethrough and into contiguous capillaries. The deployment instruments are arranged to pierce the tissue of the myocardium from either the endocardium or the epicardium to insert the inserts into the myocardium, depending on the particular deployment instrument used. The deployment instruments may make use of a stabilizing device to stabilize them during the procedure of inserting the inserts into the myocardium. A controller may also be provided as part of the system to coordinate the operation of the deployment instrument with the cardiac cycle. The formation of the lumens can be achieved either by the inserts or by some other means, such as a piercing tip or an energy applicator forming a portion of the instrument. The inserts may include one or more of pharmaceuticals, biologically active agents, radiopaque materials, etc.

RELATED APPLICATIONS

This application is a Continuation of our earlier filed U.S. patentapplication Ser. No. 10/301,007, filed on Nov. 21, 2002, entitledTransmyocardial Revascularization System And Method Of Use, which is inturn a Divisional of our earlier filed U.S. patent application Ser. No.09/773,855, filed on Feb. 1, 2001, entitled TransmyocardialRevascularization System And Method Of Use, now U.S. Pat. No. 6,514,271,which is in turn a Continuation of our earlier filed U.S. patentapplication Ser. No. 09/369,107, filed on Aug. 5, 1999 entitledTransmyocardial Revascularization And Method Of Use, now U.S. Pat. No.6,203,556, which in turn is a Continuation of our earlier filed U.S.patent application Ser. No. 08/958,788, filed on Oct. 29, 1997, entitledTransmyocardial Revascularization System, now U.S. Pat. No. 5,980,548,all of whose disclosures are incorporated by reference herein, and whichare assigned to the same assignee as the subject invention.

BACKGROUND OF THE INVENTION

This invention relates generally to medical systems and procedures andmore particularly to systems and procedures for effectingrevascularization of the myocardium of a living being.

Atherosclerosis is the leading cause of death in the industrial worldtoday. During the disease process, atherosclerotic plaques develop atvarious locations within the arterial system of those affected. Theseplaques restrict the flow of blood through the affected vessels. Ofparticular concern is when these plaques develop within the bloodvessels that feed the muscles of the heart. In healthy hearts, cardiacblood perfusion results from the two coronary arterial vessels, the leftand right coronary arteries which perfuse the myocardium from theepicardial surface inward towards the endocardium. The blood flowsthrough the capillary system into the coronary veins and into the rightatrium via the coronary sinus. When atherosclerosis occurs within thearteries of the heart it leads to myocardial infarctions, or heartattacks, and ischemia due to reduced blood flow to the heart muscle.

Over the past few years numerous methods for treating cardiovasculardisease have become available. Traditional methods utilize open surgicalprocedures to access the heart and bypass blockages in the coronaryblood vessels. In these procedures, the patient's heart is surgicallyexposed and one or more coronary arteries are replaced/bypassed withsynthetic or natural bypass grafts. During conventional cardiac surgery,the heart is stopped using cardioplegia solutions and the patient is puton cardiopulmonary bypass which uses a heart-lung machine to maintaincirculation throughout the body during the surgical procedure. A stateof hypothermia is induced in the heart tissue during the bypassprocedure to preserve the tissue from necrosis. Once the procedure iscomplete, the heart is resuscitated and the patient is removed frombypass. There are great risks associated with these surgical proceduressuch as significant pain, extended rehabilitation times, and high riskof mortality for the patient. The procedure is time-consuming and costlyto perform. This surgery also requires that the patient have bothadequate lung and kidney function in order to tolerate the circulatorybypass associated with the procedure and a number of patients which aremedically unstable are thus not a candidate for bypass surgery. As aresult, over the past few years minimally invasive techniques forperforming bypass surgery have been developed and in some instances theneed for cardiopulmonary bypass and extended recovery times are avoided.In addition, as an alternative to surgical methods, non-surgicalprocedures, such as percutaneous transluminal coronary angioplasty,rotational atherectomy, and stenting have been successfully used totreat this disease in a less invasive non-surgical fashion.

In balloon angioplasty a long, thin catheter containing a tinyinflatable balloon at its distal end is threaded through thecardiovascular system until the balloon is located at the location ofthe narrowed blood vessel. The balloon is then inflated to compress theobstructing plaque against the arterial wall, thereby restoring orimproving the flow of blood to the local and distal tissues. Rotationalatherectomy utilizes a similarly long and thin catheter, but with arotational cutting tip at its distal end for cutting through theoccluding material. Stenting utilizes a balloon tipped catheter toexpand a small coil-spring-like scaffold at the site of the blockage tohold the blood vessel open. While many patients are successfullyrelieved of their symptoms and pain, in a significant number ofpatients, the blood vessels eventually reocclude within a relativelyshort period of time. In addition, for a large number of patients thatis in the later stages of ischemic heart disease, the current technologyoffers little hope for long term cure. In these patients even extendingthe patient's life for several months provides a significant benefit tothe patients and their families.

Although these non-surgical procedures are much less costly and lesstraumatic to the patient than coronary bypass surgery there are a numberof patients for which these procedures are not suitable. For certaintypes of patients the presence of extremely diffuse steno tic lesionsand total occlusion in tortuous vessels prohibits them from beingcandidates. In addition to these procedures which attempt to reopen orbypass the coronary vessels, direct myocardial revascularization hasbeen performed by inducing the creation of new channels, other than thecoronary arteries themselves, to supply oxygenated blood and removewaste products from the heart tissue. Myocardial revascularization is atechnique used to supplement the blood supply delivered to the heart byproviding the ischemic inner surface of the heart, known as theendocardium, with direct access to the blood within the ventricularchamber. Typically the endocardium receives its nutrient blood supplyentirely from the coronary arteries that branch through the heart wallfrom the outer surface known as the epicardium.

In an article entitled “New Concepts In Revascularization Of Myocardium”by Mirhoseini et al. in Ann. Thor. Surg., 45: 415-420, April, 1988 thework of investigators exploring several different approaches for directrevascularization of ischemic myocardium is discussed. Onerevascularization technique utilizes “myoepexy”, which consistsofroughening of the myocardial surface to enhance capillarization.Another technique, known as “omentopexy”, consists of sewing the omentumover the heart to provide a new blood supply. Another approach involvesimplanting the left internal mammary artery directly into heart muscleso that blood flowing through the side branches of the artery willperfuse the muscle.

Similar revascularization techniques have involved the use ofpolyethylene tubes, endocardial incisions, and the creation ofperforated or bored channels with various types of needles, and needleacupuncture. For example, T-shaped tubes have been implanted in themuscle, with the leg of the T-tube extending into the ventricular cavityas reported by Massimo et al. in an article entitled “MyocardialRevascularization By A New Method of Carrying Blood Directly From TheLeft Ventricular Cavity Into The Coronary Circulation” appearing in J.Thorac. Surg., 34: 257-264, August, 1957. In an article entitled“Experimental Method For Producing A Collageral Circulation To The HeartDirectly From The Left Ventricle” by Goldman et al. in the Journal ofThoracic and Cardiovascular Surgery, 31: 364-374, March, 1965, severalexperimental methods for myocardial revascularization are described. Onemethod involved the implantation of excised perforated carotid arteriesinto the left ventricular wall. Goldman et al. also examined the use ofimplanted perforated polyethylene tubing in a similar fashion.

Needle acupuncture approaches to direct myocardial revascularizationhave been made and were based upon the premise that the heart ofreptiles achieve myocardial perfusion via small channels between theleft ventricle and the coronary arterial tree as described by Sen et al.in their article entitled “Transmyocardial Acupuncture: A New ApproachTo Myocardial Revascularization” in the Journal of Thoracic andCardiovascular Surgery, 50: 181-187, August, 1965. In that article itwas reported that researchers attempted to duplicate the reptiliananatomy to provide for better perfusion in human myocardium byperforating portions of the ventricular myocardium with 1.2 mm diameterneedles in 20 locations per square centimeter. It has been shown thatthe perfusion channels formed by mechanical methods such as acupuncturegenerally close within two or three months due to fibrosis and scarring.As a result these types of mechanical approaches have been abandoned infavor of the use of lasers to effect the transmyocardialrevascularization (TMR).

U.S. Pat. No. 5,591,159 (Taheri) describes a device for effectingmyocardial perfusion that utilizes slit needles to perforate themyocardium. The needles may also utilize a laser beam directed throughthe lumens of the needles. The device uses a trans-femoral approach toposition the device into the left ventricle of the patient. A plunger isactivated to cause the needles to enter the myocardium several times.Perforation of the myocardium may be effected by means of a laser beamthrough the lumen of the needle or high velocity drill.

U.S. Pat. No. 5,655,548 (Nelson et al.) describes a method for perfusingthe myocardium using a conduit disposed between the left ventricle andthe coronary sinus. In one method, an opening is formed between the leftventricle and the coronary sinus, and the coronary ostium is partiallyoccluded using a stent that prevents the pressure in the coronary sinusfrom exceeding a predetermined value. Blood ejected from the leftventricle enters the coronary sinus during cardiac systole. Theapparatus limits the peak pressure in the coronary sinus to minimizeedema of the venous system. The system utilizes retroperfusion via thecoronary since of the venous system.

Previous researchers had explored long term retroperfusion via thecoronary sinus but found that it leads to edema of the cardiac veinswhich are incapable of sustaining long-term pressures above about 60 mmHg. The procedure basically places a stent-like plug in the leftventricle so that blood flows into the coronary sinus and then into themyocardium via the venous system using retroperfusion, not into themyocardium directly. In the aforementioned Nelson et al. patent there isdisclosed the use of a cutting instrument, such as a cannulated needle,a rotating blade, or medical laser to provide the required opening forthe conduit. It is believed that when implanted in the heart, the plugand stent will result in long-term retrograde perfusion of themyocardium using the cardiac venous system and will cause aredistribution of the flow within the venous system so that a greaterfraction of the deoxygenated blood will exit through the lymphatic stemand the Thebasian veins. The inventors also describe the use of aconduit which takes the place of the coronary sinus.

U.S. Pat. No. 4,658,817 (Hardy) describes a surgical carbon dioxidelaser with a hollow needle mounted on the forward end of the handpiece.The needle is used to perforate a portion of the tissue, for instancethe epicardium, to provide the laser beam direct access to distal tissueof the endocardium for lasering and vaporization. The device does notvaporize the tissue of the outer wall instead it separates the tissuewhich recoils to its native position after the needle's removal. Thistechnique eliminates surface bleeding and the need for suturing theepicardium as is done with other techniques.

In U.S. Pat. No. 5,607,421 (Jeevanandam) discloses that laser channelsremain open because carbonization associated with the laser energyinhibits lymphocyte, macrophage, and fibroblast migration. Thus, incontrast to channels created by needle acupuncture, laser channels healmore slowly and with less scar formation which allows endothelializationand long term patency.

It has been reported by Moosdorf et al. in their article entitled“Transmyocardial Laser Revascularization—Morphologoic PathophysiologicAnd Historical Principles Of Indirect Revascularization Of The HeartMuscle” in Z Kardiol, 86(3): 147-164, March, 1997 that thetransmyocardial laser revascularization results in a relevant reductionof clinical symptoms such as angina and an increase of exercise capacityin approximately two thirds of the patients treated. Objective data ofenhanced myocardial perfusion as assessed by positron emissiontomography, thallium scans, and stress echocardiography has also beenpresented in other studies. Some researchers have found that TMRchannels created by CO2 lasers are surrounded by a zone of necrosis withan extent of about 500 microns. In heart patients who died in the earlypostoperative period (1 to 7 days) almost all channels were closed byfibrin clots, erythrocytes, and macrophages. At 150 days post procedure,they observed a string of cicatricial tissue admixed with a polymorphousblood-filled capillary network and small veins, which very rarely hadcontinuous links to the left ventricular cavity. At the 2 week postprocedure point a granular tissue with high macrophage and monocyteactivity was observable. See for example, the article by Krabatsch etal. entitled “Histological Findings After Transmyocardial LaserRevascularization” appearing in J. Card. Surg. 11: 326-331, 1996, andthe article by Gassler et al. entitled “Transmyocardial LaserRevascularization. Historical Features in Human Nonresponder Myocardium”appearing in Circulation, 95(2): 371-375, Jan. 21, 1997.

In summary, there are a number of potential mechanisms whichindividually or in combination may be responsible for the improvementsseen in patients subject to the previously described myocardialrevascularization techniques including: (1) new blood flow throughcreated channels, (2) angiogenesis (stimulation of the creation of newblood vessels), (3) cardiac denervation, (4) the placebo effect, and (5)ablation of ischemic myocardium.

Currently it is believed that cardiac denervation and angiogenesis arethe primary causes for post procedure angina relief and improvedperfusion respectively. The injury stimulates vasculargenesis and thelaser energy damages nerves thereby minimizing the pain sensation. Thelasers are however very expensive to purchase.

While the aforementioned techniques and methods for revascularizing themyocardium offer some promise they nevertheless suffer from onedisadvantage or another.

OBJECTS OF THE INVENTION

Accordingly, it is a general object of this invention to provide atransmyocardial revascularization system which overcomes thedisadvantages of the prior art.

It is a further object of this invention to provide a system andmethodology for providing relief from ischemic myocardium.

It is a further object of this invention to provide apparatus andmethods for providing myocardial perfusion that reduce the level ofischemia in a patient.

It is a further object of this invention to provide methods andapparatus for myocardial revascularization to reduce the level ofdiscomfort associated with angina in a patient.

It is a further object of this invention to provide a device and methodto enable patients that suffer from the later stages of ischemic heartdisease to experience reduced pain and improved emotional well-being.

It is a further object of this invention to provide a transmyocardialrevascularization system and methodology which is simple and costeffective.

It is a further object of this invention to provide an apparatus andmethod for myocardial revascularization to increase blood flow to themyocardium from the endocardium without using the native diseasedcoronary arteries.

It is a further object of this invention to provide an apparatus andmethod for myocardial revascularization to be used with patients havingextensive coronary atherosclerosis in whom a bypass surgery is notindicated.

It is a further object of this invention is to provide a device andtechnique for endovascular myocardial revascularization.

It is another object of the present invention to provide methods andapparatus which can be utilized either in open surgical, minimallyinvasive surgical, or transluminal techniques to perfuse the myocardium.

It is a further object of this invention to provide direct myocardialrevascularization without the need for opening the chest cavity.

It is a further object of this invention to provide direct endovascularmyocardial revascularization without having to utilize a laser (althougha laser may be used, if desired in some applications as part of theprocedure).

SUMMARY OF THE INVENTION

These and other objects of this invention are achieved by providing acardiac vascularization system and methods of revascularizing themyocardium. The system basically comprises at least one, and preferablya plurality of elongated small diameter inserts for introduction atspaced locations from one another in the wall of the myocardium. Theinserts are formed of a material to elicit a foreign body or healingresponse to cause the formation of lumens in communication with thearterial system. The inserts may be totally resorbable, partiallyresorbable or non-resorbable, and in the case of the latter may beremovable from the myocardium after the formation of the lumens.

In accordance with various preferred embodiments of the invention thesystem also includes various deployment instruments for deploying theinserts into the wall of the myocardium. Some instruments are arrangedto introduce the inserts into the myocardium via either the pericardium,while other instruments are arranged to introduce the inserts into themyocardium via the endocardium.

The deployment instruments maybe configured to form the lumens bymechanical action or by the application of energy, e.g., electrical,thermal, sonic, radiation, etc., or some biological agent to themyocardium. The inserts themselves or in combination with deploymentinstrument can be used to form the lumens.

In accordance with one aspect of the invention the system may includemeans to stabilize the deployment instrument during the formation and/orinsertion of the inserts into the myocardium. In addition control meansmay be provided to coordinate the operation of the deployment instrumentwith the cardiac cycle.

DESCRIPTION OF THE DRAWING

Other objects and many attendant features of this invention will becomereadily appreciated as the same becomes better understood by referenceto the following detailed description when considered in connection withthe accompanying drawing wherein:

FIG. 1 is an illustration of the heart of a living human being showingone embodiment of a deployment instrument forming a portion of themyocardial revascularization system of the subject invention being usedto deploy plural inserts constructed in accordance with this inventioninto the myocardium via the pericardium;

FIG. 2 is an illustration similar to that of FIG. 1, but showing anotherembodiment of a deployment instrument forming a portion of themyocardial revascularization system of the subject invention being usedto deploy those inserts into the myocardium via the epicardium;

FIG. 3 is an enlarged illustration of the heart of a living human beingshowing the inserts of the system of FIG. 1 in place fully embedded inthe wall of the myocardium;

FIG. 4 is a side elevational view, partially in section, of analternative embodiment of an insert and an alternative deploymentinstrument forming an alternative embodiment of a system constructed inaccordance with this invention;

FIG. 5 is a side elevational view, partially in section, showing anotherportion of the deployment instrument of the embodiment of the systemshown in FIG. 4;

FIG. 6 is a side elevational view, partially in section, showing thedeployment of the insert of FIG. 4 into the wall of the myocardium bythe deployment instrument of FIGS. 4 and 5;

FIG. 7 is a side elevational view, partially in section, showing theinsert of FIGS. 4-6 when fully deployed in the wall of the myocardium;

FIG. 8 is an enlarged isometric view of the distal end of the insertshown in FIGS. 4-7;

FIGS. 9A-9S are each isometric views of respective alternativeembodiments of inserts constructed in accordance with this invention;

FIGS. 10A-10D are each side elevation views, partially in section, ofvarious exemplary inserts of the subject invention shown in place withinthe wall of the myocardium;

FIG. 11 is a block and schematic diagram showing one embodiment of thesystem of the subject invention and including means to control theoperation thereof in accordance with the cardiac cycle;

FIG. 12 is a diagram like that of FIG. 11 but showing the addition of amechanism, e.g., a vacuum hood, for use with a deployment instrument ofthis invention to stabilize the deployment instrument with respect tothe myocardium;

FIG. 13 is an illustration of a portion of the wall of a healthy heartshowing its vascularity;

FIG. 14 is an illustration, like that of FIG. 13, but showing a wallwhose vasculature has been reduced over time by atherosclerosis, e.g.,the branches of its coronary arteries are fully or partially occludedand many of the capillaries in the myocardium have atrophied;

FIG. 15 is an illustration, like that of FIG. 14, but showing the wallof the heart immediately after deployment of an insert of the system ofthis invention in the myocardium to increase the flow of blood from theventricle via the lumen in which the insert is located to tissue andcapillaries contiguous with the lumen;

FIG. 16 is an illustration, like that of FIG. 15, but showing the wallof the heart some time after the deployment of an insert so that theinsert has elicited a foreign body response in the myocardium tissue tostimulate angiogenesis and revascularization, whereupon the increasedflow of blood in one portion of a vessel can provide added blood toneighboring tissues and capillaries; and

FIG. 17 is an illustration, like that of FIG. 16, but showing the wallof the heart at some later time (i.e., after the insert has beenabsorbed or has been removed from its lumen), whereupon the lumen mayshrink in diameter but may remain patent to carry blood to contiguoustissue and capillaries, including the recently grown vasculature, tothereby provide a beneficial blood supply to the myocardium.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawing where like reference numerals refer to likeparts there is shown in FIG. 1 a transmyocardial revascularizationsystem 20 constructed in accordance with this invention shown in theprocess of revascularizing the myocardium of a living, e.g., human,being. In FIG. 13 there is shown, by way of an illustration (not toscale), a section of the wall of the left ventricle of a healthy humanheart 1. As can be seen therein the wall includes the epicardium 2, themyocardium 3, the endocardium 4, two unoccluded branches 5 and 6 of acoronary artery and extensive associated vasculature, e.g., capillaries7. In FIG. 14 the illustration is of the same portion of the wall of theventricle, but showing the effects of atherosclerosis, i.e., lesions orplaque deposits 8, in the branch vessels 5 and 6 and atrophiedvasculature 7.

The revascularization systems of this invention are particularlysuitable for revascularizing the myocardium whose blood supply has beendiminished by atherosclerosis (like that shown in FIG. 14) or by otherdisease processes. Moreover, the subject invention contemplates variousdifferent systems and preferred ones of those systems will be describedin detail later. Suffice it for now to state that each systemconstructed in accordance with this invention includes at least one, andpreferably, a plurality of elongated inserts 22 (designated by thegeneral reference number 22 in FIG. 1) and a deployment instrument(e.g., instrument 24 of FIG. 1) for deploying the insert(s) into themyocardium. Various alternative inserts 22A-22S are shown in FIGS.9A-9S, respectively.

In accordance with one preferred embodiment of a system the deploymentinstrument 24 utilizes a piercing member (to be described later) locatedadjacent its distal end to create plural channels or lumens 9 (FIGS. 1and 15) in the wall of the myocardium 3 at spaced locations from oneanother and into which respective inserts (e.g., inserts 22 of FIG. 1)are deployed. Other means can be utilized to form the channels or lumens9. For example the system may include means, e.g., as part of thedeployment instrument or some other device, for providing a suitablebiological agent to the myocardium and associated tissue (e.g.,endocardium or epicardium) to produce or form a lumen in the myocardium.Alternatively, the deployment instrument can provide one or more ofvarious types of energy to that tissue to create the lumen(s) and thenthe insert(s) can be deployed therein. Examples of various types ofenergy contemplated for such a procedure are thermal energy, mechanicalenergy (e.g., rotational cutting or boring, slicing, etc.), electricalenergy (e.g., radio frequency energy), hydraulic energy, pneumaticenergy, vibratory energy (e.g., sonic, ultrasonic, etc.) radiationenergy, laser or other light energy, or other types of electromagneticenergy, etc. It should be pointed out at this juncture that theapplication of energy to the cardiac tissue not only serves to createthe lumen(s) 9 for the insert(s) 22 and 22A-22S, but can also disablelocal nerves (denervation) to minimize patient pain resulting fromangina.

It should also be pointed out that the formation of the channels orlumens 9 in the myocardium and associated tissue can be accomplished bymeans other than the insert-deployment instrument 24. In this regard thesubject invention contemplates that the inserts themselves can beconstructed so that they can be used to pierce or otherwise penetrateinto the wall of the myocardium to form the lumens. In such applicationsthe formation of the lumens is accomplished at the same time that theinserts are deployed therein.

Irrespective of how the lumens 9 are formed, the inserts can be insertedinto the wall of the myocardium 3 and into the lumens (or to form thelumens), via either a transthoracic approach to the epicardium 2 (seeFIG. 1) or by a percutaneous transvascular, e.g., transfemoral, approachto the endocardium 4 (see FIG. 2). When the lumens are formed bytransthoracic approach they are preferably made sufficiently deep tocommunicate with the interior of the ventricle. However, for some typeof myocardial revascularization procedures communication of the lumenwith the ventricular chamber is not necessary, as will be describedlater.

When the lumen(s) is(are) in communication with the ventricular chamberand the insert(s) is(are) in place within those lumens, the insert(s)serve(s) to hold the lumen(s) open and allow blood to flow into thelumen(s) from the ventricular chamber, whereupon that blood can nourishtissue and capillaries in the myocardium contiguous with the lumen.

In accordance with a preferred aspect of this invention, the inserts areformed of a material so that when they are in place they serve toinitiate a “foreign body” or “healing response” in the local (i.e.,contiguous) tissue, whereupon the inserts can be removed or absorbedthereafter, leaving the lumens patent to supply blood to contiguoustissue, capillaries and additional vasculature (e.g., new capillaries)which have grown over time by virtue of the process of angiogenesis.This action ensures that the myocardium receives an increased bloodsupply over that which it received prior to the subject transmyocardialrevascularization (TMR) procedure.

Even where the lumen(s) formed do not communicate with the interior ofthe ventricular chamber, its (their) formation and the deployment of theinsert(s) therein still has an advantageous effect insofar as providingbeneficial blood flow to the myocardium is concerned. In this regard theformation of a lumen and the deployment of an insert therein serves tobridge those capillaries which are contiguous with the lumen. Thus,blood can be carried from capillaries in one portion of the myocardiumto capillaries in a remote portion thereof by the lumen bridging thosecapillaries. In addition, over time the healing response and resultantangiogenesis induced by the presence of the inserts in the lumen willincrease the myocardial vasculature, thereby further benefiting thepatient.

In some applications it may be desirable to stabilize the deploymentinstrument against the endocardium or epicardium during therevascularization procedure. For such applications the system makes useof some releasable securement or attachment means, such as a suctionhood (to be described later) to stabilize or otherwise hold thedeployment instrument in place. Once positioned, the instrument can beactivated to advance the piercing member or to direct energy into thecardiac tissue to create the lumen and to introduce an insert therein.

In some applications, depth control means (also to be described later)may be provided to limit the depth of penetration of the insert(s) intothe myocardium. The depth control means may comprise means to limit thedepth of the lumen(s) created by the instrument, or may comprise meanson the insert itself to limit its depth of penetration into the lumen ormay be a combination of both.

In some applications, e.g., where the deployment instrument applieselectrical energy to the cardiac tissue to form the lumen(s) or whereformation of the lumen(s) and/or deployment of the insert(s) therein isbest accomplished during a particular portion of the cardiac cycle, thesystem may also include some control and sensing means (also to bedescribed later) that synchronizes the operation of the deploymentinstrument to a specific portion of the cardiac cycle.

As will also be described later, the inserts 22 and 22A-22R are ofvarious shapes, e.g., solid, tubular, trough-like, helical(spring-shaped), filament, or ribbon-like members, etc. They may be ofany suitable biocompatible material, and may be formed of one or moreresorbable materials so as to be either partially or totally resorbable.Examples of suitable resorbable materials are polyglycolic acid,polydiaxonone, polycaprolactone, collagen, hyaluronic acid, a polymercomposite and/or oxidized regenerated cellulose.

Referring again to FIG. 1 the details of the system 20 as shown thereinwill now be discussed. As mentioned earlier that system comprises adeployment instrument 24 and plural inserts 22. The instrument 24 itselfbasically comprises an elongated central wire 26 having pointed orotherwise sharp distal end or piercing tip 28. A flange 30 projectsoutward from the periphery of the wire 26 a short distance proximally ofthe tip 28. The insert 22 is a tubular member which is arranged to bedisposed and frictionally held on the wire 28 between the flange 30 andthe tip 28 so that it can be carried by the wire 26 into the epicardiumand underlying myocardium by the application of a force in the distaldirection on the wire. In this regard the proximal end (not shown) ofthe wire 28 is coupled to means (also not shown) arranged to have apushing force applied thereto by either manual action or by somecomponent, e.g., a motor or other actuator, under control of a controlsystem 52, like that shown I FIG. 11. This pushing action causes the tip28 of the wire 26 to pierce through the epicardium and underlyingmyocardium to form a lumen 9 with further advancement of the wire 26 inthe distal direction carrying the insert into the lumen 9.

As mentioned above, the embodiment of the insert shown in FIG. 1 anddesignated by the reference number 22 basically comprises a smalldiameter, elongated tubular member. That member is similar to the insertshown in FIG. 9A, and as best seen therein has a central channel orpassageway 32 through which the wire 26 may pass when the insert ismounted thereon. The insert also includes plural apertures 34 in thewall forming it and which are in fluid communication with the passageway32, for the reasons to be described later. An optional flange may beprovided about the periphery at the proximal end 36 of the tubularinsert as shown in FIG. 9A. The flange serves as a stop to engagecardiac tissue to preclude the insert from being inserted too deep intothe myocardium. Insert 22 does not include the flange. The distal end 38of insert 22 is open and is in communication with the passageway 32.

The insert 22 may be formed of any of the aforementioned resorbablematerials so that it will be absorbed over time leaving a lumen 9 likethat shown in FIG. 17. Alternatively it may be formed of anon-resorbable material. In that case it may be preferable that theinsert be removable after some time to leave a lumen 9 like shown inFIG. 17.

When the insert 22 is located on the deployment instrument's wire 26 itsproximal end 36 (FIG. 9) is in abutment with the flange 30 on the wireand with the piercing tip 28 of the wire extending out of the distal end38 of the insert as shown in FIG. 1. As mentioned above, the proximalend of the wire 26 is coupled to means to have a pushing force appliedthereto manually or under control of a control system 52 like that shownin FIG. 11 or 12. This pushing action causes the tip 28 of the wire 26to pierce through the epicardium and underlying myocardium to start toform a lumen 9. At the same time the flange 30 on the wire abuts theproximal end 36 of the insert to push the insert along with it to carrythe insert into the lumen 9 as it is formed. The stop on the insert (ifincorporated into the insert) or the flange 30 of the wire 26 isarranged to enable the proximal end of the insert to pass through theepicardium and just slightly into the underlying myocardium and with thelength of the insert 22 being selected so that the open distal end 38 ofthe insert just enters the ventricle. To that end, the length of theinsert is preferably selected to be consistent with the thickness of themyocardium into which it is implanted. In order to accommodate variousthicknesses of myocardia, the inserts of the subject invention may bepre-cut to any length in the range of approximately 0.6 cm to 2.0 cm inlength. Moreover, for typical application the inserts preferably have anoutside diameter in the range of approximately 1.5 mm to 2.5 mm and aninside diameter in the range of approximately 1.0 to 2.0 mm.

In order to stabilize the deployment instrument 24 during the lumenforming-insert deployment procedure, the device 24 of the system maybeconstructed like shown in FIGS. 1 and 12 to include a releasablysecurable attachment mechanism in the form of a suction hood 40 andassociated components. The suction hood 40 basically comprises anelongate tube 42 having a central passageway 44 for accommodating theinsert deployment wire 26 with the insert 22 mounted on the distal endthereof. An enlarged flange 46 extends about the periphery of the distalend of the tube 42 for engagement with the epicardium. A source ofvacuum 48 (FIG. 12) is coupled to the proximal end of the tube 42. Thevacuum source is arranged to be actuated by operation of the operatorcontrol 50 (FIG. 12). This action couples the vacuum source 48 to theinterior of the tube 42 to produce suction at the distal end of the hoodto hold the hood in place on the pericardium centered over the locationat which an insert is to be deployed. The operator control 50 can thenbe activated to cause the control system 52 and its various componentsto operate to effect the pushing of the deployment instrument's wire 26(with the insert 22 mounted thereon) distally into the epicardium andunderlying myocardium, as discussed above.

If it is desired to time the introduction of the insert 22 into themyocardium to any particular portion of the cardiac cycle, e.g., duringdiastole, then the system may include use of a cardiac cycle monitor 54and an associated cardiac sensor 56. The cardiac sensor 56 can be anysuitable conventional device for providing an electrical signalindicative of the cardiac cycle. The cardiac cycle monitor is responsiveto the sensor for providing signals to the control system 52, whichcontrols the operation of the deployment instrument in coordination withthe sensed cardiac cycle. Thus, the control system initiates theoperation of means in the system, coupled to the wire 26 to push thewire distally at a predetermined point in the cardiac cycle.

After each of the inserts 22 has been deployed into the myocardium, theinstrument is removed, i.e., the wire 26 extracted, and the insert 22left in place. Thus, since the distal end 38 of the insert 22 is openand in fluid communication with the interior of the left ventricle bloodfrom the left ventricular chamber can flow into the distal end of theinsert and be carried down its central passageway 32 and out through theapertures 34 into the adjacent myocardial tissue and capillaries. Sincethe proximal end of the insert is preferably located just under theepicardium, when the insertion wire 26 is withdrawn the puncture in theepicardium through which the insertion wire passed will close off andhemostasis will occur shortly thereafter. This action will prevent theleakage of blood out of the lumen 9 through the epicardium.

As will be appreciated by those skilled in the art the shape of theinsert 22 (as well as all of other inserts of this invention) will keepthe lumen 9 in which it is located open to the flow of bloodtherethrough. Over time the body's natural healing response to the“foreign” insert deployed within the lumen 9 will result in increasedvasculature contiguous with the lumen, like shown in FIG. 17. It shouldbe noted that in FIG. 17 the relevant cardiac portion is shown after theinsert has either been absorbed or removed, but the result is the same,namely, the formation of new capillaries and vessels as a result of thebody's natural healing response and angiogenesis caused by the one-timepresence of the insert within the lumen.

In FIGS. 15-17 the revascularization of the myocardium of anatherosclerotic diseased heart is illustrated. In particular, in FIG. 16there is shown the same portion of the heart shown in FIG. 14, anddescribed earlier, but after a lumen 9 has been formed in the myocardiumand an alternative embodiment of an insert located within that lumen.The alternative insert is the embodiment of the insert shown in FIG. 9Mand designated by the reference number 22M. The details of this insertwill be described later. Suffice it for now to state that insert 22M isin the form of a cylindrical coil or helix and has been inserted a lumen9 formed in the same manner as described earlier. Since the insert 22Mis a helix, it will hold the lumen 9 open and in communication with theinterior of the ventricle at its distal end. Moreover, blood can flowinto the lumen through the center of the insert 22M and out through thespaces between contiguous coils to feed the contiguous myocardial tissueand capillaries. On the short term any capillaries which receive bloodfrom the lumen 9 can carry that blood to remote locations, therebynourishing the tissue at such remote locations by the delivery of moreblood thereto than prior to the procedure. Over time the body's naturalhealing response and angiogenesis will result in increased vasculature,such as shown in FIG. 16.

FIG. 17 shows the condition after angiogenesis has occurred to createsignificant new vasculature, e.g., capillaries 7, and the insert 22either has been removed or resorbed by the body. The resorption orremoval of the insert from the lumen, so that the insert is no longerpresent to hold the lumen open, may permit the lumen to shrink orotherwise decrease somewhat in diameter, as illustrated in FIG. 17, oreventually close. Even if the lumen 9 eventually closes there will stillbe some beneficial effect since the tissue contiguous with the lumen 9will be more highly vascularized than prior to the insertion of theinsert due to the elicited angiogenesis.

As should be appreciated from the foregoing whether the system 20 makesuse of non-resorbable or resorbable inserts is of little relevance fromthe standpoint of immediately increased blood flow to the myocardiumtissue and capillaries contiguous with the lumens so long as the insertsare constructed to enable blood to flow therethrough or therearound inthe lumens from the interior of the ventricular chamber. If, however,the inserts are constructed so that they do not allow blood to flowtherethrough or therearound within the lumens, then the beneficialeffects, e.g., increased vasculative, of the inserts will not likelyarise until after they have induced the natural healing response in themyocardium and have been absorbed or otherwise removed from themyocardium.

It should be pointed out at this juncture that for some applications theinserts may be constructed so that they do not extend into communicationwith the ventricular chamber to permit blood to flow from the ventricleinto the lumen. One such alternative arrangement is shown in FIG. 3. Inthat illustration the inserts 22 are shown as being fully located(embedded) within the myocardium. Since there will be no blood flow intothe lumens from the ventricular chamber, this arrangement will not serveto immediately increase the amount of blood available to the myocardiumtissue in which the inserts 22 are located. However, if the inserts areconstructed so that blood can flow either through them (e.g., theinclude a longitudinal passageway and sidewall apertures like thosedescribed earlier, or are porous, etc.) or around them within the lumen,then blood from tissue and/or capillaries contiguous with one portion ofthe lumen 9 can be carried to other portions of the lumen and the tissueand capillaries contiguous therewith. Thus, the presence of the insertsin the lumens may serve to bring blood from one portion of themyocardium to other portions. Moreover, the angiogenesis actionresulting by the location of the inserts within the lumens over timewill further revascularize the myocardium.

In FIG. 2, a system 100 constructed in accordance with this invention isshown during the process of revascularizing the myocardium via atransvascular access to the endocardium and myocardium. The system 100comprises a small diameter, flexible deployment instrument 102 and oneor more inserts constructed like those described heretofore. Inparticular, in the example shown in FIG. 2, the inserts used are theinserts 22. The instrument 102 comprises an outer tube or catheter 104,an inner tube 106, and a flexible wire 108. The wire 108 has a pointeddistal end or piercing tip 110. The catheter 104 includes a centralpassageway 112 extending down its length and terminating at a free endin the form of a rounded or non-sharp tip 114. The inner tube 106 isdisposed within the passageway 112 and is movable longitudinally withrespect to the catheter 104. The inner tube 106 includes a centralpassageway through which the wire 108 extends, with the tip 110 of thewire extending beyond the free end 116 of the inner tube by a distancejust slightly greater than the length of an insert 22.

The insert 22 is located on the extending portion of the wire 108 asshown in FIG. 2. When introduced through the vascular system and intothe heart the inner tube 106 and wire 108 are fully retracted within thecatheter 104 but located adjacent its tip 114. The rounded tip 114 ofthe catheter serves as the end of the instrument 102 to facilitate itssafe guidance to the operative position shown in FIG. 2. At that timethe inner (pusher) tube 106 with the 108 extending therethrough ispushed distally by some means, e.g., manually or by some activatorforming a portion of the control system 52, so that the wire's tip 110penetrates through the endocardium and into the myocardium. Thecontinued pushing action forms the lumen and carries the insert into thelumen 9 in a similar manner as described earlier. When the insert is inthe desired position within the myocardium the wire 108 is retractedwith respect to the inner tube 106 until it no longer is within theinsert, thereby depositing the insert within the lumen 9. The instrumentcan then be used to deploy other inserts 22 in the same manner, and onceall have been deployed the instrument is retracted as a unit from theheart and out of the associated vascular access path.

In FIGS. 4-8 there is shown another alternative system 200 (FIG. 5) foreffecting the revascularization of the myocardium. The system 200 is ofmanual type and basically comprises at least one insert 22R, like thatshown in FIG. 9R, and a manually operated deployment instrument 202 fordeploying the insert in a lumen in the myocardium. The insert 22Rbasically comprises a resorbable suture 204 or other flexible filamenthaving a distal end at which a barbed resorbable anchor 206 is fixedlysecured. The anchor includes a rounded distal end 208 (FIG. 8) fromwhich plural fingers 210 project backward. The fingers may be somewhatflexible to facilitate the disposition of the insert within theinstrument 202 (as will be described later).

The instrument 202 basically comprises a pusher member 212 and a piercermember 214. The pusher member 212 is in the form of a small diametertube having a tapered distal end 216, a flanged proximal end 218 forminga cap, and a central passageway 220 extending therebetween. The sutureor filament portion 204 of the insert 22R is located within thepassageway 220, with the anchor 206 being located immediately distallyof the tapered distal end 216 of the pusher as shown in FIG. 4.

The piercer member is a small diameter tube having a bias-cut distal endto form a piercing tip 224, a flanged proximal end forming a handle 226,and a central passageway 228 extending therebetween. The entrance to thepassageway 228 is flared at 230. The inside diameter of the passageway228 is slightly greater than the outside diameter of the pusher member204 so that the pusher member can be located therein, with the fingers210 of the anchor position 206 of the insert 22R flexed radially inwardto enable the anchor to fit within the passageway 228 as shown in FIG.5.

The instrument 202 is particularly suitable for transthoracicintroduction into the myocardium 3. To that end the instrument 202 isassembled as shown in FIG. 5 and manipulated (i.e., pushed distally)such that the needle's piercing tip 224 pierces the epicardium 2 andenters to a desired depth into the myocardium 3 to form a lumen 9. Asshown in FIG. 6 the depth of penetration is less than the thickness ofthe myocardium so that the lumen 9 is not in communication with theinterior of the ventricular chamber (although it could extend therein,if desired). Stop means (not shown) forming a portion of the instrument202 can be provided to establish the desired depth of cardiacpenetration.

Once the piercer member is at the desired depth, the cap 218 of thepusher member is pushed distally with respect to piercer member's handle226 to extend the insert's anchor 206 into the lumen tract, whereuponthe freeing of the anchor's fingers 210 allows them to flex outwardly asshown in FIG. 6. The pusher member 212 and the piercer member 214 arethen withdrawn as a unit proximally, so that the filament portion 204 isfreed leaving the insert in place like shown in FIG. 7. The anchor orthe insert serves to secure it within the lumen 9 resistant toaccidental dislodgment during the deployment procedure. It should bepointed out that the anchor can take various forms, e.g., be a rigidbarb-like member lacerated on the outer portion of the insert or it canbe an activatable pivoting member (not shown) similar in construction tothat used on a conventional clothing label tag, or any other suitableconstruction.

The filament portion 204 may consist of a solid filament, such as a PGAsuture, or a strip of material, such as collagen or Gelfoam, or may benon-resorbable, like Gortex. In any case the material for the filamentportion 204 is selected to initiate a foreign body reaction to stimulatearteriogenesis in a manner similar to that described earlier.

It must be pointed out at this juncture that each insert of thisinvention is preferably configured such that its, presence in themyocardial tissue does not significantly limit the contractility of thecardiac muscle, although as will be described later some embodimentsprovide less resistance to cardiac contractility than others. Moreover,the inserts may be coated with or contain growth factors, anti-oxidants,seeded cells, or other drug biologically active components dependingupon the result desired.

Referring now to FIGS. 9A to 9S, the details of other insertsconstructed in accordance with this invention will be described. Theseinserts are merely exemplary of many other inserts which can beconstructed to accomplish the ends of this invention.

The embodiment of the insert 22A shown in FIG. 9A is a tubular structurewith axial perforations 34 for allowing blood to pass through thelongitudinal passageway 32 and to pass through the lateral perforations34 into the adjacent myocardium.

The embodiment of the insert 22B shown in FIG. 9B is a trough-likestructure 60 with slots 62 in the marginal edges to form fins forholding the lumen 9 open. The slots 62 allow more contact of the bloodto the neighboring myocardium. The tip 64 is sharpened to facilitate thedeployment, e.g., it helps pierce the cardiac tissue during deployment.

The embodiment of the insert 22C shown in FIG. 9C is a simpletrough-like structure 66, that is relatively easy to manufacture, e.g.,can be made by die cutting a rectangular sheet and forming the sheetaround a pin.

The embodiment of the insert 22D shown in FIG. 9D comprises a porouswalled tube 68, with a longitudinal passage 70 extending down its centerand whose distal end 72 is open.

The embodiment of the insert 22E shown in FIG. 9E is a series of tubularcylindrical sections 74 that are connected by flexible filaments 76.This structure effectively stents the lumen opening and allows theinsert to freely contract and expand along the longitudinal axis andtherefore conform to the contraction of the myocardium during thecardiac cycle.

The embodiment of the insert 22F shown in FIG. 9F is formed of severalspherical beads 78 spaced on a flexible filament 76. The filament alsoincorporates a T-shaped distal end in the form of anchor member 82 toaid in placement or securement. This insert also effectively stents thelumen and allows the insert to freely contract and expand along thelongitudinal axis and therefore conform to the contraction of themyocardium during the cardiac cycle.

The embodiment of the insert 22G shown in FIG. 9G is similar to thatshown in FIG. 9F except that the periodically spaced barb structures 82extend outward from the filament 80 at spaced locations. Thisarrangement may better anchor the insert in the myocardium and may alsoallow for better fluid communication past each barb structure along thelength of the lumen 9 than the embodiment 22F of FIG. 9F.

The embodiment of the insert 22H shown in FIG. 9H is a cylindricalporous material tube 68 with a proximal end in the form of a shoulder 84to limit penetration. This particular embodiment appears best suited forinsertion from the endocardium into the myocardium, whereupon theshoulder 84 anchors the opening of the insert at the ventricle.

The embodiment of the insert 22I in FIG. 9I is a flexible woven tube 86having plural equidistantly spaced reinforcing rings 88. The wovenportions of the tube are porous to allow blood to pass from the innerpassageway 90 for communication with the blood vessels and capillariescontiguous with the other lumen 9. The reinforcing rings 88 support theinsert and the adjacent myocardium to keep the lumen from collapsing.

The embodiments of the inserts 22J, 22K, and 22L shown in FIGS. 9J, 9Kand 9L, respectively, consist of flexible ribbon-like structures 22 withanchors 94, 96, and 98, respectively, on the distal end for locating andsecuring the inserts into the myocardium. The ribbon-like material canbe formed of materials such as woven dacron, polyglycolic acid, cotton,silk, and collagen. The ribbon-like tail of these embodiments can bemade extra long and after implantation during a surgical approachwhatever portion extends from the epicardium can be trimmed off (seeFIG. 10B). The anchor portion can be formed by insert molding the anchorcomponent onto the filament structure. The main feature of theseconstructions is to stimulate a foreign body reaction and a healingresponse which results in the formation of capillaries at the site ofthe implant. As such, these structures will provide less of a short termimprovement to vascularization, but instead will lead to a long termimprovement.

The embodiment of the inserts 22M, 22N, and 22O shown in FIGS. 9M, 9N,and 9O, respectively, consists of helical coil-like structures 120. Theimplants can be formed of such materials as stainless steel, nitinol,titanium or such material as polyglycolic acid or polylactic acid. Theembodiments are flexible, particularly with respect to theirlongitudinal axis and as such will readily deform longitudinally inconjunction with the cardiac cycle of the myocardium. These structuresserve to stent the lumen 9 and allow for excellent fluid communicationbetween the lumen 9 and the adjacent blood vessels. The embodimentsshown in 9N and 9O have anchoring portions at their respective distalends which can be used to locate and secure the inserts in themyocardium. In particular, the insert 22N includes a hook-like member122 at its distal end, whereas the insert 220 includes a plate-likeanchor 124 at its distal end.

The embodiment of the insert 22P shown in FIG. 9P is a flexiblefilament-like member 126 with a stiffened distal end portion bent backover itself for anchoring the insert into the myocardium. This insertfunctions in a similar manner to the inserts of embodiments 22J, 22K and22L.

The embodiment of the insert 22Q shown in FIG. 9Q is a perforatedcylinder member, similar to insert 22A but with tongue-like member 130at the proximal end of the cylinder to form a shoulder. The shoulderserves to limit the depth of placement of the insert into themyocardium. This particular embodiment is particularly suited to beingplaced through the epicardium into the myocardium. The bulbous portionof the shoulder limits the depth of penetration into the myocardium andthe epicardium seals around it to prohibit leakage from the channel pastthe epicardium like shown in FIG. 10D.

The embodiment of the insert 22R shown in FIG. 9R has been describedearlier. This insert 22R functions in a similar manner to inserts 22J,22K and 22L. Moreover, the filament-like tails of these embodiments canbe made extra long to be trimmed off in a similar manner to thatdescribed earlier with reference to inserts 22J, 22K and 22L. Thefilament can be formed of Dacron, polyester, silk, polyglycolic acid,collagen, or some other such suitable material. The main feature ofthese constructions is to stimulate a foreign body reaction and ahealing response which results in the formation of capillaries at thesite of the implant. As such, these structures will provide less of ashort term improvement to vascularization, but instead will lead to along term improvement.

The embodiment of the insert 22S shown in FIG. 9S is a “flowable” insertcomprised of a flowable material 132, such as collagen paste,cyanoacrylate (glue/adhesive), thrombin glue, growth factor gelatin,etc. The flowable material can be stored in a tube (not shown) anddispensed into the puncture tract by a needle-like device, such as asyringe (not shown). The flowable material can be designed to hardenslightly after placement, like an epoxy or silicon caulking material, sothat it is not extruded from the puncture during the cardiac contractioncycle. A main feature of this construction is to stimulate a foreignbody reaction and a healing response which results in the formation ofcapillaries at the site of the implant. As such, the insert 22S willprovide less of a short term improvement to vascularization, but insteadwill lead to a long term improvement.

In FIGS. 10A to 10D various of the inserts described above are shown inplace in the myocardium to cause the body to initiate a healing responsein tissue contiguous with the lumen, as described heretofore. The tissueat which the foreign healing response occurs at initially is designatedby the reference number 11 in those figures. While not shown in FIGS.10A-10D, additional or new vasculature results in the myocardial tissueas a result of angiogenesis.

Without further elaboration the foregoing will so fully illustrate ourinvention that others may, by applying current or future knowledge,adopt the same for use under various conditions of service.

1. A system for vascularizing the myocardium and/or associated tissue ofa living being to produce at least one lumen in communication with thebeing's arterial system, said system comprising a plurality of insertsand a delivery system, said inserts comprising cells, said deliverysystem comprising channel producing means arranged for creating at leastone channel in the myocardium and/or associated tissue, said deliverysystem arranged to deposit said inserts into the at least one channel.2. The system of claim 1 wherein said at least one lumen is a new bloodcarrying vessel and wherein said cells inserts deposited in the at leastone channel are operative to produce the new blood carrying vessel. 3.The system of claim 1 wherein said inserts effect revascularization ofthe myocardium and/or associated tissue by the formation of a new bloodcarrying vessel.
 4. The system of claim 1 wherein said cells are coatedon said insert.
 5. The system of claim 2 wherein said inserts serve toelicit a healing response in the myocardium and/or associated tissue. 6.The system of claim 1 wherein at least a portion of at least one of saidinserts additionally comprises one or more of drugs, pharmaceuticals,biologically active materials, growth factors, radio-opaque materialsand antioxidants.
 7. The system of claim 1 wherein at least a portion ofat least one of said inserts is at least partially resorbable.
 8. Thesystem of claim 7 wherein said portion of said at least one of saidinserts comprises polyglycolic acid, polydiaxonone, polycaprolactone,collagen, hyaluronic acid, oxidized regenerated cellulose, or polymercomposites.
 9. The system of claim 1 wherein said channel producingmeans comprises piercing means.
 10. The system of claim 9 wherein saidpiercing means comprises a mechanical means.
 11. The system of claim 10wherein said mechanical means comprises rotational cutting, boring,puncturing, or slicing.
 12. The system of claim 9 wherein said piercingmeans comprises energy application means.
 13. The system of claim 12wherein said energy application means provides energy selected from thegroup consisting of one or more of electrical, thermal, electromagnetic,vibratory, hydraulic, pneumatic, and radiation.
 14. The system of claim1 wherein said channel producing means is arranged for creating pluralchannels in the myocardium and/or associated tissue and wherein saiddelivery system is arranged to deposit said inserts into the pluralchannels.
 15. The system of claim 1 additionally comprising depthlimitation means.
 16. The system of claim 1 additionally comprisingstabilizing means.
 17. The system of claim 1 additionally comprisingcontroller means to coordinate deployment of said inserts with thecardiac cycle.
 18. The system of claim 1 wherein said delivery system isarranged to introduce said inserts via a transthoracic route.
 19. Thesystem of claim 1 wherein said delivery system is arranged to introducesaid inserts via a percutaneous transvascular route.
 20. A method ofrevascularizing the myocardium and/or associated tissue of a livingbeing comprising: (a) providing at least one insert comprising cells;(b) providing a delivery system for said at least one insert, saiddelivery system comprising channel producing means; (c) operating saidchannel producing means to create at least one channel in the myocardiumand/or associated tissue; and (d) introducing said at least one insertinto said at least one channel.
 21. The method of claim 20 wherein saiddelivery system creates plural channels in the myocardium and/orassociated tissue, said method comprising providing plural inserts, eachinsert of which comprising cells, and introducing said inserts intorespective ones of said plural channels.
 22. The method of claim 20wherein said introduction of said at least one insert into said channelresults in the formation of a new blood carrying vessel coupled to thebeing's arterial system.
 23. The method of claim 22 wherein said atleast one insert serves to elicit a healing response in said myocardiumand/or associated tissue.
 24. The system of claim 23 wherein seeded cellstructure of said at least one insert comprises cells which causesrevascularization of the myocardium, and/or associated by forming a newblood carrying vessel.